""" command line options, ini-file and conftest.py processing. """
import argparse
import copy
import inspect
import os
import shlex
import sys
import types
import warnings
from functools import lru_cache
from types import TracebackType
from typing import Any
from typing import Callable
from typing import Dict
from typing import List
from typing import Optional
from typing import Sequence
from typing import Set
from typing import Tuple
from typing import Union

import attr
import py
from packaging.version import Version
from pluggy import HookimplMarker
from pluggy import HookspecMarker
from pluggy import PluginManager

import _pytest._code
import _pytest.assertion
import _pytest.deprecated
import _pytest.hookspec  # the extension point definitions
from .exceptions import PrintHelp
from .exceptions import UsageError
from .findpaths import determine_setup
from .findpaths import exists
from _pytest._code import ExceptionInfo
from _pytest._code import filter_traceback
from _pytest.compat import importlib_metadata
from _pytest.outcomes import fail
from _pytest.outcomes import Skipped
from _pytest.pathlib import Path
from _pytest.warning_types import PytestConfigWarning

if False:  # TYPE_CHECKING
    from typing import Type


hookimpl = HookimplMarker("pytest")
hookspec = HookspecMarker("pytest")


class ConftestImportFailure(Exception):
    def __init__(self, path, excinfo):
        Exception.__init__(self, path, excinfo)
        self.path = path
        self.excinfo = excinfo  # type: Tuple[Type[Exception], Exception, TracebackType]


def main(args=None, plugins=None) -> "Union[int, _pytest.main.ExitCode]":
    """ return exit code, after performing an in-process test run.

    :arg args: list of command line arguments.

    :arg plugins: list of plugin objects to be auto-registered during
                  initialization.
    """
    from _pytest.main import ExitCode

    try:
        try:
            config = _prepareconfig(args, plugins)
        except ConftestImportFailure as e:
            exc_info = ExceptionInfo(e.excinfo)
            tw = py.io.TerminalWriter(sys.stderr)
            tw.line(
                "ImportError while loading conftest '{e.path}'.".format(e=e), red=True
            )
            exc_info.traceback = exc_info.traceback.filter(filter_traceback)
            exc_repr = (
                exc_info.getrepr(style="short", chain=False)
                if exc_info.traceback
                else exc_info.exconly()
            )
            formatted_tb = str(exc_repr)
            for line in formatted_tb.splitlines():
                tw.line(line.rstrip(), red=True)
            return ExitCode.USAGE_ERROR
        else:
            try:
                ret = config.hook.pytest_cmdline_main(
                    config=config
                )  # type: Union[ExitCode, int]
                try:
                    return ExitCode(ret)
                except ValueError:
                    return ret
            finally:
                config._ensure_unconfigure()
    except UsageError as e:
        tw = py.io.TerminalWriter(sys.stderr)
        for msg in e.args:
            tw.line("ERROR: {}\n".format(msg), red=True)
        return ExitCode.USAGE_ERROR


class cmdline:  # compatibility namespace
    main = staticmethod(main)


def filename_arg(path, optname):
    """ Argparse type validator for filename arguments.

    :path: path of filename
    :optname: name of the option
    """
    if os.path.isdir(path):
        raise UsageError("{} must be a filename, given: {}".format(optname, path))
    return path


def directory_arg(path, optname):
    """Argparse type validator for directory arguments.

    :path: path of directory
    :optname: name of the option
    """
    if not os.path.isdir(path):
        raise UsageError("{} must be a directory, given: {}".format(optname, path))
    return path


# Plugins that cannot be disabled via "-p no:X" currently.
essential_plugins = (
    "mark",
    "main",
    "runner",
    "fixtures",
    "helpconfig",  # Provides -p.
)

default_plugins = essential_plugins + (
    "python",
    "terminal",
    "debugging",
    "unittest",
    "capture",
    "skipping",
    "tmpdir",
    "monkeypatch",
    "recwarn",
    "pastebin",
    "nose",
    "assertion",
    "junitxml",
    "resultlog",
    "doctest",
    "cacheprovider",
    "freeze_support",
    "setuponly",
    "setupplan",
    "stepwise",
    "warnings",
    "logging",
    "reports",
    "faulthandler",
)

builtin_plugins = set(default_plugins)
builtin_plugins.add("pytester")


def get_config(args=None, plugins=None):
    # subsequent calls to main will create a fresh instance
    pluginmanager = PytestPluginManager()
    config = Config(
        pluginmanager,
        invocation_params=Config.InvocationParams(
            args=args or (), plugins=plugins, dir=Path().resolve()
        ),
    )

    if args is not None:
        # Handle any "-p no:plugin" args.
        pluginmanager.consider_preparse(args)

    for spec in default_plugins:
        pluginmanager.import_plugin(spec)
    return config


def get_plugin_manager():
    """
    Obtain a new instance of the
    :py:class:`_pytest.config.PytestPluginManager`, with default plugins
    already loaded.

    This function can be used by integration with other tools, like hooking
    into pytest to run tests into an IDE.
    """
    return get_config().pluginmanager


def _prepareconfig(args=None, plugins=None):
    if args is None:
        args = sys.argv[1:]
    elif isinstance(args, py.path.local):
        args = [str(args)]
    elif not isinstance(args, (tuple, list)):
        msg = "`args` parameter expected to be a list or tuple of strings, got: {!r} (type: {})"
        raise TypeError(msg.format(args, type(args)))

    config = get_config(args, plugins)
    pluginmanager = config.pluginmanager
    try:
        if plugins:
            for plugin in plugins:
                if isinstance(plugin, str):
                    pluginmanager.consider_pluginarg(plugin)
                else:
                    pluginmanager.register(plugin)
        return pluginmanager.hook.pytest_cmdline_parse(
            pluginmanager=pluginmanager, args=args
        )
    except BaseException:
        config._ensure_unconfigure()
        raise


def _fail_on_non_top_pytest_plugins(conftestpath, confcutdir):
    msg = (
        "Defining 'pytest_plugins' in a non-top-level conftest is no longer supported:\n"
        "It affects the entire test suite instead of just below the conftest as expected.\n"
        "  {}\n"
        "Please move it to a top level conftest file at the rootdir:\n"
        "  {}\n"
        "For more information, visit:\n"
        "  https://docs.pytest.org/en/latest/deprecations.html#pytest-plugins-in-non-top-level-conftest-files"
    )
    fail(msg.format(conftestpath, confcutdir), pytrace=False)


class PytestPluginManager(PluginManager):
    """
    Overwrites :py:class:`pluggy.PluginManager <pluggy.PluginManager>` to add pytest-specific
    functionality:

    * loading plugins from the command line, ``PYTEST_PLUGINS`` env variable and
      ``pytest_plugins`` global variables found in plugins being loaded;
    * ``conftest.py`` loading during start-up;
    """

    def __init__(self):
        super().__init__("pytest")
        # The objects are module objects, only used generically.
        self._conftest_plugins = set()  # type: Set[object]

        # state related to local conftest plugins
        # Maps a py.path.local to a list of module objects.
        self._dirpath2confmods = {}  # type: Dict[Any, List[object]]
        # Maps a py.path.local to a module object.
        self._conftestpath2mod = {}  # type: Dict[Any, object]
        self._confcutdir = None
        self._noconftest = False
        # Set of py.path.local's.
        self._duplicatepaths = set()  # type: Set[Any]

        self.add_hookspecs(_pytest.hookspec)
        self.register(self)
        if os.environ.get("PYTEST_DEBUG"):
            err = sys.stderr
            encoding = getattr(err, "encoding", "utf8")
            try:
                err = py.io.dupfile(err, encoding=encoding)
            except Exception:
                pass
            self.trace.root.setwriter(err.write)
            self.enable_tracing()

        # Config._consider_importhook will set a real object if required.
        self.rewrite_hook = _pytest.assertion.DummyRewriteHook()
        # Used to know when we are importing conftests after the pytest_configure stage
        self._configured = False

    def parse_hookimpl_opts(self, plugin, name):
        # pytest hooks are always prefixed with pytest_
        # so we avoid accessing possibly non-readable attributes
        # (see issue #1073)
        if not name.startswith("pytest_"):
            return
        # ignore names which can not be hooks
        if name == "pytest_plugins":
            return

        method = getattr(plugin, name)
        opts = super().parse_hookimpl_opts(plugin, name)

        # consider only actual functions for hooks (#3775)
        if not inspect.isroutine(method):
            return

        # collect unmarked hooks as long as they have the `pytest_' prefix
        if opts is None and name.startswith("pytest_"):
            opts = {}
        if opts is not None:
            # TODO: DeprecationWarning, people should use hookimpl
            # https://github.com/pytest-dev/pytest/issues/4562
            known_marks = {m.name for m in getattr(method, "pytestmark", [])}

            for name in ("tryfirst", "trylast", "optionalhook", "hookwrapper"):
                opts.setdefault(name, hasattr(method, name) or name in known_marks)
        return opts

    def parse_hookspec_opts(self, module_or_class, name):
        opts = super().parse_hookspec_opts(module_or_class, name)
        if opts is None:
            method = getattr(module_or_class, name)

            if name.startswith("pytest_"):
                # todo: deprecate hookspec hacks
                # https://github.com/pytest-dev/pytest/issues/4562
                known_marks = {m.name for m in getattr(method, "pytestmark", [])}
                opts = {
                    "firstresult": hasattr(method, "firstresult")
                    or "firstresult" in known_marks,
                    "historic": hasattr(method, "historic")
                    or "historic" in known_marks,
                }
        return opts

    def register(self, plugin, name=None):
        if name in _pytest.deprecated.DEPRECATED_EXTERNAL_PLUGINS:
            warnings.warn(
                PytestConfigWarning(
                    "{} plugin has been merged into the core, "
                    "please remove it from your requirements.".format(
                        name.replace("_", "-")
                    )
                )
            )
            return
        ret = super().register(plugin, name)
        if ret:
            self.hook.pytest_plugin_registered.call_historic(
                kwargs=dict(plugin=plugin, manager=self)
            )

            if isinstance(plugin, types.ModuleType):
                self.consider_module(plugin)
        return ret

    def getplugin(self, name):
        # support deprecated naming because plugins (xdist e.g.) use it
        return self.get_plugin(name)

    def hasplugin(self, name):
        """Return True if the plugin with the given name is registered."""
        return bool(self.get_plugin(name))

    def pytest_configure(self, config):
        # XXX now that the pluginmanager exposes hookimpl(tryfirst...)
        # we should remove tryfirst/trylast as markers
        config.addinivalue_line(
            "markers",
            "tryfirst: mark a hook implementation function such that the "
            "plugin machinery will try to call it first/as early as possible.",
        )
        config.addinivalue_line(
            "markers",
            "trylast: mark a hook implementation function such that the "
            "plugin machinery will try to call it last/as late as possible.",
        )
        self._configured = True

    #
    # internal API for local conftest plugin handling
    #
    def _set_initial_conftests(self, namespace):
        """ load initial conftest files given a preparsed "namespace".
            As conftest files may add their own command line options
            which have arguments ('--my-opt somepath') we might get some
            false positives.  All builtin and 3rd party plugins will have
            been loaded, however, so common options will not confuse our logic
            here.
        """
        current = py.path.local()
        self._confcutdir = (
            current.join(namespace.confcutdir, abs=True)
            if namespace.confcutdir
            else None
        )
        self._noconftest = namespace.noconftest
        self._using_pyargs = namespace.pyargs
        testpaths = namespace.file_or_dir
        foundanchor = False
        for path in testpaths:
            path = str(path)
            # remove node-id syntax
            i = path.find("::")
            if i != -1:
                path = path[:i]
            anchor = current.join(path, abs=1)
            if exists(anchor):  # we found some file object
                self._try_load_conftest(anchor)
                foundanchor = True
        if not foundanchor:
            self._try_load_conftest(current)

    def _try_load_conftest(self, anchor):
        self._getconftestmodules(anchor)
        # let's also consider test* subdirs
        if anchor.check(dir=1):
            for x in anchor.listdir("test*"):
                if x.check(dir=1):
                    self._getconftestmodules(x)

    @lru_cache(maxsize=128)
    def _getconftestmodules(self, path):
        if self._noconftest:
            return []

        if path.isfile():
            directory = path.dirpath()
        else:
            directory = path

        # XXX these days we may rather want to use config.rootdir
        # and allow users to opt into looking into the rootdir parent
        # directories instead of requiring to specify confcutdir
        clist = []
        for parent in directory.realpath().parts():
            if self._confcutdir and self._confcutdir.relto(parent):
                continue
            conftestpath = parent.join("conftest.py")
            if conftestpath.isfile():
                mod = self._importconftest(conftestpath)
                clist.append(mod)
        self._dirpath2confmods[directory] = clist
        return clist

    def _rget_with_confmod(self, name, path):
        modules = self._getconftestmodules(path)
        for mod in reversed(modules):
            try:
                return mod, getattr(mod, name)
            except AttributeError:
                continue
        raise KeyError(name)

    def _importconftest(self, conftestpath):
        # Use a resolved Path object as key to avoid loading the same conftest twice
        # with build systems that create build directories containing
        # symlinks to actual files.
        # Using Path().resolve() is better than py.path.realpath because
        # it resolves to the correct path/drive in case-insensitive file systems (#5792)
        key = Path(str(conftestpath)).resolve()
        try:
            return self._conftestpath2mod[key]
        except KeyError:
            pkgpath = conftestpath.pypkgpath()
            if pkgpath is None:
                _ensure_removed_sysmodule(conftestpath.purebasename)
            try:
                mod = conftestpath.pyimport()
                if (
                    hasattr(mod, "pytest_plugins")
                    and self._configured
                    and not self._using_pyargs
                ):
                    _fail_on_non_top_pytest_plugins(conftestpath, self._confcutdir)
            except Exception:
                raise ConftestImportFailure(conftestpath, sys.exc_info())

            self._conftest_plugins.add(mod)
            self._conftestpath2mod[key] = mod
            dirpath = conftestpath.dirpath()
            if dirpath in self._dirpath2confmods:
                for path, mods in self._dirpath2confmods.items():
                    if path and path.relto(dirpath) or path == dirpath:
                        assert mod not in mods
                        mods.append(mod)
            self.trace("loaded conftestmodule %r" % (mod))
            self.consider_conftest(mod)
            return mod

    #
    # API for bootstrapping plugin loading
    #
    #

    def consider_preparse(self, args):
        i = 0
        n = len(args)
        while i < n:
            opt = args[i]
            i += 1
            if isinstance(opt, str):
                if opt == "-p":
                    try:
                        parg = args[i]
                    except IndexError:
                        return
                    i += 1
                elif opt.startswith("-p"):
                    parg = opt[2:]
                else:
                    continue
                self.consider_pluginarg(parg)

    def consider_pluginarg(self, arg):
        if arg.startswith("no:"):
            name = arg[3:]
            if name in essential_plugins:
                raise UsageError("plugin %s cannot be disabled" % name)

            # PR #4304 : remove stepwise if cacheprovider is blocked
            if name == "cacheprovider":
                self.set_blocked("stepwise")
                self.set_blocked("pytest_stepwise")

            self.set_blocked(name)
            if not name.startswith("pytest_"):
                self.set_blocked("pytest_" + name)
        else:
            name = arg
            # Unblock the plugin.  None indicates that it has been blocked.
            # There is no interface with pluggy for this.
            if self._name2plugin.get(name, -1) is None:
                del self._name2plugin[name]
            if not name.startswith("pytest_"):
                if self._name2plugin.get("pytest_" + name, -1) is None:
                    del self._name2plugin["pytest_" + name]
            self.import_plugin(arg, consider_entry_points=True)

    def consider_conftest(self, conftestmodule):
        self.register(conftestmodule, name=conftestmodule.__file__)

    def consider_env(self):
        self._import_plugin_specs(os.environ.get("PYTEST_PLUGINS"))

    def consider_module(self, mod):
        self._import_plugin_specs(getattr(mod, "pytest_plugins", []))

    def _import_plugin_specs(self, spec):
        plugins = _get_plugin_specs_as_list(spec)
        for import_spec in plugins:
            self.import_plugin(import_spec)

    def import_plugin(self, modname, consider_entry_points=False):
        """
        Imports a plugin with ``modname``. If ``consider_entry_points`` is True, entry point
        names are also considered to find a plugin.
        """
        # most often modname refers to builtin modules, e.g. "pytester",
        # "terminal" or "capture".  Those plugins are registered under their
        # basename for historic purposes but must be imported with the
        # _pytest prefix.
        assert isinstance(modname, str), (
            "module name as text required, got %r" % modname
        )
        modname = str(modname)
        if self.is_blocked(modname) or self.get_plugin(modname) is not None:
            return

        importspec = "_pytest." + modname if modname in builtin_plugins else modname
        self.rewrite_hook.mark_rewrite(importspec)

        if consider_entry_points:
            loaded = self.load_setuptools_entrypoints("pytest11", name=modname)
            if loaded:
                return

        try:
            __import__(importspec)
        except ImportError as e:
            new_exc_message = 'Error importing plugin "{}": {}'.format(
                modname, str(e.args[0])
            )
            new_exc = ImportError(new_exc_message)
            tb = sys.exc_info()[2]

            raise new_exc.with_traceback(tb)

        except Skipped as e:
            from _pytest.warnings import _issue_warning_captured

            _issue_warning_captured(
                PytestConfigWarning("skipped plugin {!r}: {}".format(modname, e.msg)),
                self.hook,
                stacklevel=1,
            )
        else:
            mod = sys.modules[importspec]
            self.register(mod, modname)


def _get_plugin_specs_as_list(specs):
    """
    Parses a list of "plugin specs" and returns a list of plugin names.

    Plugin specs can be given as a list of strings separated by "," or already as a list/tuple in
    which case it is returned as a list. Specs can also be `None` in which case an
    empty list is returned.
    """
    if specs is not None and not isinstance(specs, types.ModuleType):
        if isinstance(specs, str):
            specs = specs.split(",") if specs else []
        if not isinstance(specs, (list, tuple)):
            raise UsageError(
                "Plugin specs must be a ','-separated string or a "
                "list/tuple of strings for plugin names. Given: %r" % specs
            )
        return list(specs)
    return []


def _ensure_removed_sysmodule(modname):
    try:
        del sys.modules[modname]
    except KeyError:
        pass


class Notset:
    def __repr__(self):
        return "<NOTSET>"


notset = Notset()


def _iter_rewritable_modules(package_files):
    for fn in package_files:
        is_simple_module = "/" not in fn and fn.endswith(".py")
        is_package = fn.count("/") == 1 and fn.endswith("__init__.py")
        if is_simple_module:
            module_name, _ = os.path.splitext(fn)
            yield module_name
        elif is_package:
            package_name = os.path.dirname(fn)
            yield package_name


class Config:
    """
    Access to configuration values, pluginmanager and plugin hooks.

    :ivar PytestPluginManager pluginmanager: the plugin manager handles plugin registration and hook invocation.

    :ivar argparse.Namespace option: access to command line option as attributes.

    :ivar InvocationParams invocation_params:

        Object containing the parameters regarding the ``pytest.main``
        invocation.

        Contains the following read-only attributes:

        * ``args``: tuple of command-line arguments as passed to ``pytest.main()``.
        * ``plugins``: list of extra plugins, might be None.
        * ``dir``: directory where ``pytest.main()`` was invoked from.
    """

    @attr.s(frozen=True)
    class InvocationParams:
        """Holds parameters passed during ``pytest.main()``

        .. versionadded:: 5.1

        .. note::

            Note that the environment variable ``PYTEST_ADDOPTS`` and the ``addopts``
            ini option are handled by pytest, not being included in the ``args`` attribute.

            Plugins accessing ``InvocationParams`` must be aware of that.
        """

        args = attr.ib(converter=tuple)
        plugins = attr.ib()
        dir = attr.ib(type=Path)

    def __init__(self, pluginmanager, *, invocation_params=None):
        from .argparsing import Parser, FILE_OR_DIR

        if invocation_params is None:
            invocation_params = self.InvocationParams(
                args=(), plugins=None, dir=Path().resolve()
            )

        self.option = argparse.Namespace()
        self.invocation_params = invocation_params

        _a = FILE_OR_DIR
        self._parser = Parser(
            usage="%(prog)s [options] [{}] [{}] [...]".format(_a, _a),
            processopt=self._processopt,
        )
        self.pluginmanager = pluginmanager
        self.trace = self.pluginmanager.trace.root.get("config")
        self.hook = self.pluginmanager.hook
        self._inicache = {}  # type: Dict[str, Any]
        self._override_ini = ()  # type: Sequence[str]
        self._opt2dest = {}  # type: Dict[str, str]
        self._cleanup = []  # type: List[Callable[[], None]]
        self.pluginmanager.register(self, "pytestconfig")
        self._configured = False
        self.hook.pytest_addoption.call_historic(
            kwargs=dict(parser=self._parser, pluginmanager=self.pluginmanager)
        )

    @property
    def invocation_dir(self):
        """Backward compatibility"""
        return py.path.local(str(self.invocation_params.dir))

    def add_cleanup(self, func):
        """ Add a function to be called when the config object gets out of
        use (usually coninciding with pytest_unconfigure)."""
        self._cleanup.append(func)

    def _do_configure(self):
        assert not self._configured
        self._configured = True
        with warnings.catch_warnings():
            warnings.simplefilter("default")
            self.hook.pytest_configure.call_historic(kwargs=dict(config=self))

    def _ensure_unconfigure(self):
        if self._configured:
            self._configured = False
            self.hook.pytest_unconfigure(config=self)
            self.hook.pytest_configure._call_history = []
        while self._cleanup:
            fin = self._cleanup.pop()
            fin()

    def get_terminal_writer(self):
        return self.pluginmanager.get_plugin("terminalreporter")._tw

    def pytest_cmdline_parse(self, pluginmanager, args):
        try:
            self.parse(args)
        except UsageError:

            # Handle --version and --help here in a minimal fashion.
            # This gets done via helpconfig normally, but its
            # pytest_cmdline_main is not called in case of errors.
            if getattr(self.option, "version", False) or "--version" in args:
                from _pytest.helpconfig import showversion

                showversion(self)
            elif (
                getattr(self.option, "help", False) or "--help" in args or "-h" in args
            ):
                self._parser._getparser().print_help()
                sys.stdout.write(
                    "\nNOTE: displaying only minimal help due to UsageError.\n\n"
                )

            raise

        return self

    def notify_exception(self, excinfo, option=None):
        if option and getattr(option, "fulltrace", False):
            style = "long"
        else:
            style = "native"
        excrepr = excinfo.getrepr(
            funcargs=True, showlocals=getattr(option, "showlocals", False), style=style
        )
        res = self.hook.pytest_internalerror(excrepr=excrepr, excinfo=excinfo)
        if not any(res):
            for line in str(excrepr).split("\n"):
                sys.stderr.write("INTERNALERROR> %s\n" % line)
                sys.stderr.flush()

    def cwd_relative_nodeid(self, nodeid):
        # nodeid's are relative to the rootpath, compute relative to cwd
        if self.invocation_dir != self.rootdir:
            fullpath = self.rootdir.join(nodeid)
            nodeid = self.invocation_dir.bestrelpath(fullpath)
        return nodeid

    @classmethod
    def fromdictargs(cls, option_dict, args):
        """ constructor useable for subprocesses. """
        config = get_config(args)
        config.option.__dict__.update(option_dict)
        config.parse(args, addopts=False)
        for x in config.option.plugins:
            config.pluginmanager.consider_pluginarg(x)
        return config

    def _processopt(self, opt):
        for name in opt._short_opts + opt._long_opts:
            self._opt2dest[name] = opt.dest

        if hasattr(opt, "default") and opt.dest:
            if not hasattr(self.option, opt.dest):
                setattr(self.option, opt.dest, opt.default)

    @hookimpl(trylast=True)
    def pytest_load_initial_conftests(self, early_config):
        self.pluginmanager._set_initial_conftests(early_config.known_args_namespace)

    def _initini(self, args) -> None:
        ns, unknown_args = self._parser.parse_known_and_unknown_args(
            args, namespace=copy.copy(self.option)
        )
        r = determine_setup(
            ns.inifilename,
            ns.file_or_dir + unknown_args,
            rootdir_cmd_arg=ns.rootdir or None,
            config=self,
        )
        self.rootdir, self.inifile, self.inicfg = r
        self._parser.extra_info["rootdir"] = self.rootdir
        self._parser.extra_info["inifile"] = self.inifile
        self._parser.addini("addopts", "extra command line options", "args")
        self._parser.addini("minversion", "minimally required pytest version")
        self._override_ini = ns.override_ini or ()

    def _consider_importhook(self, args):
        """Install the PEP 302 import hook if using assertion rewriting.

        Needs to parse the --assert=<mode> option from the commandline
        and find all the installed plugins to mark them for rewriting
        by the importhook.
        """
        ns, unknown_args = self._parser.parse_known_and_unknown_args(args)
        mode = getattr(ns, "assertmode", "plain")
        if mode == "rewrite":
            try:
                hook = _pytest.assertion.install_importhook(self)
            except SystemError:
                mode = "plain"
            else:
                self._mark_plugins_for_rewrite(hook)
        _warn_about_missing_assertion(mode)

    def _mark_plugins_for_rewrite(self, hook):
        """
        Given an importhook, mark for rewrite any top-level
        modules or packages in the distribution package for
        all pytest plugins.
        """
        self.pluginmanager.rewrite_hook = hook

        if os.environ.get("PYTEST_DISABLE_PLUGIN_AUTOLOAD"):
            # We don't autoload from setuptools entry points, no need to continue.
            return

        package_files = (
            str(file)
            for dist in importlib_metadata.distributions()
            if any(ep.group == "pytest11" for ep in dist.entry_points)
            for file in dist.files or []
        )

        for name in _iter_rewritable_modules(package_files):
            hook.mark_rewrite(name)

    def _validate_args(self, args, via):
        """Validate known args."""
        self._parser._config_source_hint = via
        try:
            self._parser.parse_known_and_unknown_args(
                args, namespace=copy.copy(self.option)
            )
        finally:
            del self._parser._config_source_hint

        return args

    def _preparse(self, args, addopts=True):
        if addopts:
            env_addopts = os.environ.get("PYTEST_ADDOPTS", "")
            if len(env_addopts):
                args[:] = (
                    self._validate_args(shlex.split(env_addopts), "via PYTEST_ADDOPTS")
                    + args
                )
        self._initini(args)
        if addopts:
            args[:] = (
                self._validate_args(self.getini("addopts"), "via addopts config") + args
            )

        self._checkversion()
        self._consider_importhook(args)
        self.pluginmanager.consider_preparse(args)
        if not os.environ.get("PYTEST_DISABLE_PLUGIN_AUTOLOAD"):
            # Don't autoload from setuptools entry point. Only explicitly specified
            # plugins are going to be loaded.
            self.pluginmanager.load_setuptools_entrypoints("pytest11")
        self.pluginmanager.consider_env()
        self.known_args_namespace = ns = self._parser.parse_known_args(
            args, namespace=copy.copy(self.option)
        )
        if self.known_args_namespace.confcutdir is None and self.inifile:
            confcutdir = py.path.local(self.inifile).dirname
            self.known_args_namespace.confcutdir = confcutdir
        try:
            self.hook.pytest_load_initial_conftests(
                early_config=self, args=args, parser=self._parser
            )
        except ConftestImportFailure as e:
            if ns.help or ns.version:
                # we don't want to prevent --help/--version to work
                # so just let is pass and print a warning at the end
                from _pytest.warnings import _issue_warning_captured

                _issue_warning_captured(
                    PytestConfigWarning(
                        "could not load initial conftests: {}".format(e.path)
                    ),
                    self.hook,
                    stacklevel=2,
                )
            else:
                raise

    def _checkversion(self):
        import pytest

        minver = self.inicfg.get("minversion", None)
        if minver:
            if Version(minver) > Version(pytest.__version__):
                raise pytest.UsageError(
                    "%s:%d: requires pytest-%s, actual pytest-%s'"
                    % (
                        self.inicfg.config.path,
                        self.inicfg.lineof("minversion"),
                        minver,
                        pytest.__version__,
                    )
                )

    def parse(self, args, addopts=True):
        # parse given cmdline arguments into this config object.
        assert not hasattr(
            self, "args"
        ), "can only parse cmdline args at most once per Config object"
        self.hook.pytest_addhooks.call_historic(
            kwargs=dict(pluginmanager=self.pluginmanager)
        )
        self._preparse(args, addopts=addopts)
        # XXX deprecated hook:
        self.hook.pytest_cmdline_preparse(config=self, args=args)
        self._parser.after_preparse = True
        try:
            args = self._parser.parse_setoption(
                args, self.option, namespace=self.option
            )
            if not args:
                if self.invocation_dir == self.rootdir:
                    args = self.getini("testpaths")
                if not args:
                    args = [str(self.invocation_dir)]
            self.args = args
        except PrintHelp:
            pass

    def addinivalue_line(self, name, line):
        """ add a line to an ini-file option. The option must have been
        declared but might not yet be set in which case the line becomes the
        the first line in its value. """
        x = self.getini(name)
        assert isinstance(x, list)
        x.append(line)  # modifies the cached list inline

    def getini(self, name: str):
        """ return configuration value from an :ref:`ini file <inifiles>`. If the
        specified name hasn't been registered through a prior
        :py:func:`parser.addini <_pytest.config.argparsing.Parser.addini>`
        call (usually from a plugin), a ValueError is raised. """
        try:
            return self._inicache[name]
        except KeyError:
            self._inicache[name] = val = self._getini(name)
            return val

    def _getini(self, name: str) -> Any:
        try:
            description, type, default = self._parser._inidict[name]
        except KeyError:
            raise ValueError("unknown configuration value: {!r}".format(name))
        value = self._get_override_ini_value(name)
        if value is None:
            try:
                value = self.inicfg[name]
            except KeyError:
                if default is not None:
                    return default
                if type is None:
                    return ""
                return []
        if type == "pathlist":
            dp = py.path.local(self.inicfg.config.path).dirpath()
            values = []
            for relpath in shlex.split(value):
                values.append(dp.join(relpath, abs=True))
            return values
        elif type == "args":
            return shlex.split(value)
        elif type == "linelist":
            return [t for t in map(lambda x: x.strip(), value.split("\n")) if t]
        elif type == "bool":
            return bool(_strtobool(value.strip()))
        else:
            assert type is None
            return value

    def _getconftest_pathlist(self, name, path):
        try:
            mod, relroots = self.pluginmanager._rget_with_confmod(name, path)
        except KeyError:
            return None
        modpath = py.path.local(mod.__file__).dirpath()
        values = []
        for relroot in relroots:
            if not isinstance(relroot, py.path.local):
                relroot = relroot.replace("/", py.path.local.sep)
                relroot = modpath.join(relroot, abs=True)
            values.append(relroot)
        return values

    def _get_override_ini_value(self, name: str) -> Optional[str]:
        value = None
        # override_ini is a list of "ini=value" options
        # always use the last item if multiple values are set for same ini-name,
        # e.g. -o foo=bar1 -o foo=bar2 will set foo to bar2
        for ini_config in self._override_ini:
            try:
                key, user_ini_value = ini_config.split("=", 1)
            except ValueError:
                raise UsageError("-o/--override-ini expects option=value style.")
            else:
                if key == name:
                    value = user_ini_value
        return value

    def getoption(self, name: str, default=notset, skip: bool = False):
        """ return command line option value.

        :arg name: name of the option.  You may also specify
            the literal ``--OPT`` option instead of the "dest" option name.
        :arg default: default value if no option of that name exists.
        :arg skip: if True raise pytest.skip if option does not exists
            or has a None value.
        """
        name = self._opt2dest.get(name, name)
        try:
            val = getattr(self.option, name)
            if val is None and skip:
                raise AttributeError(name)
            return val
        except AttributeError:
            if default is not notset:
                return default
            if skip:
                import pytest

                pytest.skip("no {!r} option found".format(name))
            raise ValueError("no option named {!r}".format(name))

    def getvalue(self, name, path=None):
        """ (deprecated, use getoption()) """
        return self.getoption(name)

    def getvalueorskip(self, name, path=None):
        """ (deprecated, use getoption(skip=True)) """
        return self.getoption(name, skip=True)


def _assertion_supported():
    try:
        assert False
    except AssertionError:
        return True
    else:
        return False


def _warn_about_missing_assertion(mode):
    if not _assertion_supported():
        if mode == "plain":
            sys.stderr.write(
                "WARNING: ASSERTIONS ARE NOT EXECUTED"
                " and FAILING TESTS WILL PASS.  Are you"
                " using python -O?"
            )
        else:
            sys.stderr.write(
                "WARNING: assertions not in test modules or"
                " plugins will be ignored"
                " because assert statements are not executed "
                "by the underlying Python interpreter "
                "(are you using python -O?)\n"
            )


def setns(obj, dic):
    import pytest

    for name, value in dic.items():
        if isinstance(value, dict):
            mod = getattr(obj, name, None)
            if mod is None:
                modname = "pytest.%s" % name
                mod = types.ModuleType(modname)
                sys.modules[modname] = mod
                mod.__all__ = []
                setattr(obj, name, mod)
            obj.__all__.append(name)
            setns(mod, value)
        else:
            setattr(obj, name, value)
            obj.__all__.append(name)
            # if obj != pytest:
            #    pytest.__all__.append(name)
            setattr(pytest, name, value)


def create_terminal_writer(config, *args, **kwargs):
    """Create a TerminalWriter instance configured according to the options
    in the config object. Every code which requires a TerminalWriter object
    and has access to a config object should use this function.
    """
    tw = py.io.TerminalWriter(*args, **kwargs)
    if config.option.color == "yes":
        tw.hasmarkup = True
    if config.option.color == "no":
        tw.hasmarkup = False
    return tw


def _strtobool(val):
    """Convert a string representation of truth to true (1) or false (0).

    True values are 'y', 'yes', 't', 'true', 'on', and '1'; false values
    are 'n', 'no', 'f', 'false', 'off', and '0'.  Raises ValueError if
    'val' is anything else.

    .. note:: copied from distutils.util
    """
    val = val.lower()
    if val in ("y", "yes", "t", "true", "on", "1"):
        return 1
    elif val in ("n", "no", "f", "false", "off", "0"):
        return 0
    else:
        raise ValueError("invalid truth value {!r}".format(val))
